1. Technical Field
The present invention relates to a power feeder system for feeding an electric power in a non-contact manner to a power receiver provided, for example, on a mobile object such as an electric car or an electric vehicle in a track type traffic system from a power feeder provided in a track such as a railway or a road surface on which the mobile object or the like runs.
2. Description of the Related Art
Heretofore, there have been developed a various kinds of non-contact type power feeder systems for feeding an electric power to an electrically driven mobile object in a non-contact manner. The non-contact type power feeding system is adapted to charge an electric power to a power receiver from a power feeder which faces the power receiver with a gap therebetween, in a non-contact type with the use of electromagnetic induction. A vehicle in a new traffic system or the like in which the vehicle runs on a predetermined pathway with rubber tires, indispensably utilizes the above-mentioned non-contact type power feeder system in order to materialize a feeder-lineless traffic system.
Patent Document 1 (Japanese Patent Laid-Open No. 2000-152512) discloses a charging system for charging a battery mounted on a vehicle such as an electric vehicle among a various kind of vehicles. This charging system incorporates a primary coupler provided in an underground accommodation space formed by digging the ground, and an elevating means for raising the primary coupler toward a secondary coupler mounted on a vehicle so that the primary coupler is projected from the accommodation space, above the ground.
Further, Patent Document 2 (Japanese Patent Laid-Open No. 2005-269687) discloses a non-contact type charging system for a vehicle. This system is adapted to electromagnetically couple a primary coil connected to an external electric power source, with a secondary coil connected to a power battery on a vehicle so as to charge the power battery, wherein the primary coil is installed in a plane substantially flush with a road surface on which the vehicle runs, at a position where the vehicle never runs, and is raised up to a position underneath the secondary coil mounted on the vehicle. With this configuration, the repair and inspection for the charging system can be made in a comfortable posture.
The non-contact type charging system disclosed in Patent Document 1 requires a relatively long operation time for raising the primary coupler provided in the underground accommodation space toward the secondary coupler. Accordingly, this system is unsuitable for such a tract type traffic system that a quick charge should be made, within a brief time, for a vehicle which stops at a station, that is, this system can be used appropriately only for an electric vehicle.
Further, the non-contact type charging system disclosed in Patent Document 2 also requires an operation for raising the primary coil up to a level underneath the secondary coil mounted to the bottom surface of the vehicle so as to require an extra time, correspondingly. In the track type traffic system, a quick charge is required within several ten seconds during stopping at a station. The longer the time for operating the secondary coil, the shorter the charging time, the power charging becomes insufficient.
Further, the primary coil and the secondary coil have not yet been miniaturized until now, and accordingly, they cannot be installed in a narrow space. If the gap between the power feeder and the power receiver becomes larger, no high electric power can be transmitted, that is, no large gap can be taken therebetween. Thus, vertical variation of the vehicle would causes such a risk that the power feeder and the power receiver make contact with each other. Further, since the primary coil inevitably utilizes a drive mechanism, there would be caused such a problem that the overall mechanism becomes more complicate.